A stranger appears in frontier lands. Its true nature: a demon; an incubus.
Seeking to drive off this darkness, the church summons Sharon, a woman trained in the Way of Sex. However, ten nights after leaving on her mission, she had still not returned. Her successor, Alice, discovers the incubus has infiltrated a brothel. She passes herself off as a prostitute and awaits the demon. Her unease swells as she waits. Then, a man with red eyes appears.